The reason he became good at selling (according to the article) is because he changed his attitude despite reading the sales scripts verbatim both before and after his attitude adjustment.
It’s an interesting and probably helpful lesson for the startup hustlers here on HN if they can make it through this admittedly long essay.
The article states that he was fired because he did not read the script he was required to read.
Yeah, but you are, at least seemingly, missing the point: the scripts he was referring to in context weren't the legal disclosures but the sales tricks that were handed to them to use. He is pointing out that the 'elite' saleswoman wasn't better at strategy or sales tricks, but was effective because she made them feel good.
The type of person who would skip the legally required stuff while working as a telemarketer is exactly the kind of person who'd tell you he got fired for a "technicality", while he was actually fired because he was breaking the law and lying to customers.